This study compares two treatment approaches for pilonidal sinus disease: laser treatment alone versus laser treatment combined with phenol application. Pilonidal sinus is a common condition that affects young adults and can cause significant discomfort and time off work.

Participants will be randomly assigned to receive either laser treatment only (Group A) or laser treatment plus phenol application (Group B). Both treatments are minimally invasive and performed under local anesthesia as day surgery procedures.

The main goal is to determine if adding phenol to laser treatment speeds up the healing process (epithelialization) and improves patient outcomes. We will measure healing time, pain levels, return to daily activities, and quality of life over a 3-month follow-up period.

This research may help develop more effective treatment protocols that reduce healing time and improve patient comfort for people with pilonidal sinus disease.

This prospective randomized controlled clinical trial investigates whether adding crystallized phenol to laser treatment improves epithelialization and healing outcomes in patients with pilonidal sinus disease. The study will be conducted at Sancaktepe Şehit Prof. Dr. İlhan Varank Training and Research Hospital.

Study Design: 130 patients meeting inclusion criteria will be randomly assigned using computer randomization to two treatment groups (65 patients each):

Group A: Laser treatment only using SiLaC (Sinus Laser Closure) technique Group B: Combined phenol application followed by laser treatment

Treatment Procedures:

Group A receives local anesthesia, pilonidal sinus area cleaning, assessment of sinus openings, and laser probe application into sinus channels.

Group B receives local anesthesia, sinus area cleaning and curettage, crystallized phenol application into sinus channels, neutralization with saline after a specified time, followed by laser treatment.

Both groups receive standard post-operative wound care instructions and same-day discharge.

Follow-up Schedule:

Preoperative assessment Postoperative visits at 2 weeks, 4 weeks, and 3 months Clinical examination for epithelialization status Pain assessment using Visual Analog Scale (VAS 0-10) Quality of life evaluation using SF-36 questionnaire

Statistical Analysis: R software will be used for statistical analysis. Student's t-test or Mann-Whitney U test for continuous variables, chi-square test for categorical variables, and paired t-test for pre/post-treatment comparisons. Statistical significance set at p<0.05.

Primary Outcome: Time to complete epithelialization Secondary Outcomes: Postoperative pain scores, return to daily activities time, patient satisfaction, quality of life scores, and complication rates.

Inclusion Criteria:

• Age 18 years and older
• Primary pilonidal sinus disease
• Three or fewer pit counts
• Willing to participate in the study and signed informed consent form
• Able to attend follow-up visits

Exclusion Criteria:

• Age under 18 years
• More than three pit counts
• Acute abscess presentation
• Bilateral lateral extension
• Recurrent pilonidal sinus disease
• Immunocompromised patients
• Patients unable to attend follow-up visits
• Pregnancy (if applicable)
• Severe comorbidities that contraindicate surgery under local anesthesia

Open-label study due to the nature of surgical interventions which cannot be blinded to participants or care providers